• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.693-698
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• 2001

This paper establishes a coding method system including the liberation and size distribution of recycling materials in the shredder operation. Every particle in the shredded product becomes a code number using the liberation model and size distribution equation transforming of weight percentage into particles number percentage. One set of database can be obtained after all particles have been coded. This database is suitable for the size reduction operation in the process simulation of waste recycling. Coupling with the developed air classification, sizing and separating operations, the whole process simulation will be completely established for diversified application. A typical simulation for the rolling cutting shredder product of waste TV had been demonstrated under this coding system. The breakage size distribution of Gaudin and Schumann equation were selected for the shredding operation simulation. The Gaudin's liberation model was suitable fur the liberation simulation. Both of these equations were transformed weight percentage into particles distribution for the necessary of particle coding method. A better recycling operation for this shredded solid waste can be concluded from the comparison of simulation results with their sorted grade, recovery or economic of materials in different processes.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2003.11a
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• pp.198-203
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• 2003

The effects of salmon carcasses on forest and stream ecosystems were determined by nitrogen stable isotope analysis in natural streams in Hokkaido, Northern Japan, where numerous chum salmon (Oncoryhncus keta) were migrated upstream ITom ocean to spawn in autumn. The leaves and soils surrounding riparian forest and stream dwelling invertebrates were collected before and after migration. The nitrogen stable isotope ratio $({\delta}^{15}N)$ of riparian vegetation (Salix spp.) were different depending on the presence of salmon and distance from the stream. The $({\delta}^{15}N)$ of stream dwelling invertebrates were different between salmon present and absent stream. This difference was tested using the experiment channel by implanting salmon carcasses. The nitrogen stable isotope ratio of epilithic algae and leaf shredding animals were nearly 3 higher in the salmon implanted treatment suggesting that around 20％ of salmon derived nitrogen was uptake either in algae and leaf shredding invertebrates. These results suggest that the salmon carcasses effects not only on stream primary production but also on primary consumers, which decompose leaves fertilized with nitrogen from carcasses.

• Journal of Oriental Neuropsychiatry
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• v.30 no.4
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• pp.357-369
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• 2019

Objectives: This study was designed to examine the effect of Hominis Placenta Pharmacopuncture on the change in behavior, sleep-related hormones, inflammatory cytokines, anti-oxidants, weight, blood, and serum on rats given chronic physical stress. Methods: Wistar rats older than age 10 weeks were used in this experiment. They were divided into six groups. The normal group was not given stress. The control group was given only chronic physical stress and no treatment. The positive control group was given chronic physical stress and treated with zolpidem. Three Hominis Placenta Pharmacopuncture (HPP) groups were given chronic physical stress, then treated with different concentrations of HPP; HPP-0.5× (0.5 times diluted), HPP-1× (undiluted) and HPP-2× (2 times condensed). The changes of values of Nestlet Shredding results, weight, Melatonin, Gamma-aminobutylic Acid (GABA), Tumor Necrosis Factor Alpha (TNF-α), Interleukin-6 (IL-6), Superoxide dismutase (SOD), glutathione peroxidase (GPx), AST, ALT, BUN, Creatinine, and leukocytes were observed during the experiment. Results: The changes in chronic physical stress of the rat model were as follow. The Nestlet Shredding result increased in the control group compared to the normal group (p<0.05), and decreased in the HPP-1× and HPP-2× compared to the control group (p<0.05). The amount of weight gain showed increasing tendency in the HPP-2× compared to the control group since the second week. The GABA increased (p<0.05) and Melatonin also showed certain increasing tendency in the HPP-1× and HPP-2× compared to the control group. The TNF-α and IL-6 increased in the control group compared to the normal group (p<0.01), and decreased in all the HPPs compared to the control group (p<0.05). The SOD level decreased in the control group compared to the normal group (p<0.01), and increased in all the HPPs compared to the control group (p<0.05). GPx, AST, ALT, Bun, Creatinine and leukocytes showed no noticeable difference among all groups. Conclusions: Hominis Placenta Pharmacopuncture was effective in increasing weight, GABA, Melatonin, SOD, and decreasing Nestlet Shredding and inflammatory cytokines, suggesting that it consequently facilitates in relieving physical stress.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.34 no.6
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• pp.409-415
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• 2021

Medical waste management is becoming increasingly important, specifically in light of the current COVID-19 pandemic, as hospitals, clinics, quarantine centers, and medical research institutes are generating tons of medical waste every day. Previously, a traditional incineration process was utilized for managing medical waste, but the lack of landfill sites, and accompanying environmental concerns endanger public health. Consequently, an innovative sterilization shredding system was developed to resolve this problem. In this research, we focused on the design and numerical analysis of a shredding system for hazardous and infectious medical waste, to establish its operational performance. The shredding machine's components were modeled in a CAD application, and finite element analysis (FEA) was conducted using ABAQUS software. Static, fatigue, and dynamic loading conditions were used to analyze the structural stability of the cutting blade. The blade geometry proved to be effective based on the cutting force applied to shred medical waste. The dynamic stability of the structure was verified using modal analysis. Furthermore, an S-N curve was generated using a high cycle fatigue study, to predict the expected life of the cutting blade. Resultantly, an appropriate shredder system was devised to link with a sterilization unit, which could be beneficial in reducing the volume of medical waste and disposal time, thereof, thus eliminating environmental issues, and potential health hazards.

• Journal of the Korean Society for Marine Environment & Energy
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• v.10 no.3
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• pp.181-186
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• 2007

Despite of environmental problems(safety hazards), mechanical recycling of FRP boats, which involves shredding and grinding of the scrap FRP in a new product. is one of the simpler and more technically proven methods than incineration or reclamation ones. Because FRP is made up of reinforced fiber glass, it is very difficult to break into pieces. It also occurs secondary problem such as air pollution and unacceptable shredding noise level. The another urgent problem which is a serious barrier to FRP recycling is very limited reusable applications. This study is to propose a new method which is efficient and environment friendly waste FRP regenerating system. And it also have shown the polymer cement and fiber-reinforced concrete applications with the waste FRP.

• Journal of KIISE:Databases
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• v.32 no.2
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• pp.177-192
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• 2005

In this paper, we introduce a structural redundancy method. It reduces the query processing cost incurred when reconfiguring an XML document from divided XML data in shredding XML documents into relations. The fundamental idea is that query performance can be enhanced by analyzing query patterns and replicating data essential for the query performance. For the practical and effective structural redundancy, we analyzed three types of ID, VALUE, and SUBTREE replication. In addition, if given XML data and queries are very large and complex, it can be very difficult to search optimal redundancy set. Therefore, a heuristic search method is introduced in this paper. Finally, XML query processing cost arising by employing the structural redundancy, and the efficiency of proposed search method arc analyzed experimentally It is manifest that XML read query is performed more quick]y but XML update query is performed more slowly due to the additional update consistency cost for replicas. However, experimental results showed that in-place ID replication is useful even in having excessive update cost. It was also observed that multiple-place SUBTREE replication can enhance read query performance remarkably if only update cost is not excessive.

• Resources Recycling
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• v.20 no.2
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• pp.16-29
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• 2011

The Korea auto industry has developed remarkedly over the past 40 years and ranked up to 5th vehicles production nation in the world. In 2009 alone, Korea produced 3.5million vehicles and number of vehicles registered surpassed the seventeen million. On the other hand, 711 thousand ELV(End of Life Vehicles) were scrapped and used cars more than 265 thousand were exported. In the year 2009, 568 thousand tons of iron, 46 thousand tons of aluminum and 7 thousand tons of copper were recovered from ELV in Korea. Recycling ratio of ELV is approaching 95% by using ASR(Automobile Shredding Residue) as a fuel at cement kiln. Korea has enacted the automobile recycling law in 2007 and enforced it from January 2009, actually. However, the law has not been managed smoothly due to delays in the construction of infrastructure and the existence of a hostile monitoring system. In this regard, a revision and supplement program focused on recycling fee on the automobile recycling law is running under the ministry of environment now. Here, a recycling model for enhancing ELV recycling is suggested.

• International Journal of Automotive Technology
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• v.6 no.4
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• pp.413-419
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• 2005

The United States automotive recycling infrastructure has successfully reduced the amount of automotive waste sent to landfills, especially since the introduction of shredders in the late 1950s. Shredders are necessary to process and recycle automotive hulks and other durable goods. However, this industry faces significant challenges as the automotive manufacturers are increasing the use of nonmetallic components which are difficult to recycle. Additionally, it is becoming obvious that automobiles contain hazardous materials which place heavy burdens on the environment. To address this growing concern, we propose a process planning model for automotive shredders to make tactical decisions regarding at what level to process and at what level to reprocess feed stock materials. The purpose of this paper is to test analytical models to help shredders improve the profitability and efficiency of the bulk recycling processes for end of life automobile returns. The work is motivated by an actual recycling problem that was observed at Capitol City Metals shredding facility in Indianapolis, Indiana.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.890-894
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• 2003

This paper discuss basic functional construction and plant layout of a ELV dismantling system that can maximize the reusability of tarts and the recoverability of materials by dismantling ELV rationally and efficiently. "Island" type was selected for the system configuration considering processing amount, economical efficiency, and effectiveness. The system is supported by the information system, and composed of dismantling stations and handling equipments. The layout of the stations was determined after simulation and optimization using commercial software package, Arena and OptQuest. The objective of the optimization was maximum profit while the system capacity is considered as constraint. The environmental load of ELV can be minimized when the composition and function of each station are embodied in detail and the system is interfaced with shredding operation.

• Journal of Biosystems Engineering
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• v.21 no.2
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• pp.182-190
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• 1996

A macerating technique which can apply to the mechanical production system of the agricultural by-product was developed to increase the utilization of agricultural waste and solve the shortage problem in the forage supply for the livestock production. The macerating method is to shred the agricultural by-product by the two rolls which rotate at different speeds each other. The testing macerator was built and the optimum operating conditions are suggested. Results of this research are as follows: 1. The increase of the base roll speed and speed ratio between two rolls shows the better shredding index but decrease the drying rate. The optimum conditions of the base roll speed and the speed ratio between two rolls for the rice straw are 1200 rpm and 1.7-2.0 respectively. 2. The macerated alfalfa was dried to the 15%(w.b.) within 3 hrs in a field at speed ratio of rolls, 2:1 and base roll speed, 1800rpm. 3. The milled surface and straight knurled surface for the macerating roll have same effect on the drying rate of material. Both rolls have self-cleaning functions during operation.